Course detail

Machine Design - Machine Elements

FSI-5KS-K Acad. year: 2021/2022 Winter semester

The aim of the course is to provide an overview of machine parts and joints like mechanical springs, bearings, axles and shafts and bolted, riveted, welded and bonded joints. Attention is paid especially to get understanding of their function and learn the methods used in their design process. The course integrates the knowledge acquired in theoretical courses of Mechanical Engineering Bachelor's degree programme, particularly in branches of materials science and mechanics.

Language of instruction

Czech

Number of ECTS credits

5

Learning outcomes of the course unit

Getting understanding of the machine elements failures principles and causes. Knowledge of the principles of operation, design and application of the joints, shafts and their bearings, mechanical springs and pipes and fittings. Ability to apply gained knowledge to the design process of new machinery and equipment in creative way.

Prerequisites

Knowledge of design basics (drawing documentation), materials science (selection of materials), statics (load analysis), kinematics (kinematic analysis of mechanisms) and strength of materials (analysis of stress and deformation) at the level of Bachelor's degree programme aimed on mechanical engineering.

Passing the course: 4PP Strength of Materials I.

Planned learning activities and teaching methods

The course is taught through lectures explaining the basic principles and theory of the discipline. Exercises are focused on practical topics presented in lectures.

Assesment methods and criteria linked to learning outcomes

Course credit requirements: The minimum number of points needed to obtain the course credit is 15 from 30 possible. Points can be obtained based on the following criteria:
1. Student activity in tutorials.
2. Passed two written tests. The dates of the test are announced in advance, usually the tests are conducted at the middle and in the end of the semester.
The written test consists of three theorethical questions rated with one point and four computational questions rated with four points. The method of solution is assessed as well as correct result value in case of computational questions. It is possible to obtain up to 15 points from every single written test. The Mechanical engineering design textbook is not allowed by written tests. Use of any other literature during the test is not allowed as well, only calculator, pen and paper are used. Nontrivial equations are provided by teacher. If the student does not fulfill the course credit requirements, he is entitled to have a maximum of one retake test. The date of the retake test is set by the teacher, usually during the examination period. The retake test is assembled in similar way as standard written test but covers all discussed topics through course. The retake test is counted as successful at 50 % score and above.

Final exam requirements: Minimum score for passing the final test is 35 out of 70 possible points. Multiple-choice and fill-in-the-blank test is performed on the computer and it utilizes the examination system of the Institute of Mechanical and Industrial Design. The test topics cover the problems mentioned in lectures and tutorials. First part of the test consists of eleven theoretical questions, scores 2 points each. Second part of the test consists of twelve computational questions, scores 4 point each. The student has to pass the first (theoretical) part of the test to qualify himself to the second (computational) part. Each part of the final test is considered passed whether at least half of the questions are answered correctly. Each multiple-choice question has five answers, of which only one is correct. An incorrect answer does not mean negative point. In case of the fill-in-the-blank question, the student is required to fill the calculated value which is automatically assessed by the computer. A student card, pen and calculator are demanded to access the test room. The original print of the “Mechanical engineering design” textbook is allowed for the second part (computational) of the final test. Use of any other literature during the test is not allowed. The student which does not obtain the course credit is not allowed to attend the final exam.
The final score of the whole course consists of the total number of points earned from semestral project and multiple-choice test. The minimum required score is 50 points out of the maximum 100 points. The final score determines the grade according to ECTS.

Aims

The aim of the course is to provide an overview of machine parts and joints like mechanical springs, bearings, axles and shafts and bolted, riveted, welded and bonded joints. Attention is paid especially to get understanding of their function and learn the methods used in their design process. The course integrates the knowledge acquired in theoretical courses of Mechanical Engineering Bachelor's degree programme, particularly in branches of materials science and mechanics.

Specification of controlled education, way of implementation and compensation for absences

Recommended attendance at lectures, compulsory attendance at seminars (2 absences maximum). Provided lectures are based on Mechanical engineering design textbook. During the lectures the teacher refers to the specific pages in the textbook that are related to the discussed topics. Lectures are available as the electronic previews in the Moodle system. Mentioned textbook is basic material for study and preparation to final exam. There is certain number of examples discussed in each tutorial. Student must have a Mechanical engineering design textbook at tutorial classes. It is possible to use both private notebooks and computers in the classroom (WiFi available) during tutorials. Work on solution of examples could be done in the Mathcad software or other applications like MS Office Excel, etc.

The study programmes with the given course

Programme B3S-K: Engineering, Bachelor's
branch B-KSB: Quality, Reliability and Safety, compulsory

Programme B3S-K: Engineering, Bachelor's
branch B-SSZ: Machine and Equipment Construction, compulsory

Type of course unit

 

Guided consultation in combined form of studies

22 hours, compulsory

Teacher / Lecturer

Syllabus

1. Introduction to the mechanical engineering design. Failures resulting from static loading (ductile fracture).
2. Fatigue failure resulting from variable loading (fatigue fracture).
3. Shafts and axles. Joint for torque transmission.
4. Machine element surfaces. Contact of solids. Friction, lubrication and wear.
5. Power screws and threaded fasteners. Statically loaded tension joints with preload.
6. Gasketed joints. Bolted joints assembly. Fatigue loading of tension joints with preload. Riveted joints.
7. Welded, soldered and bonded joints.
8. Helical compression, extension and torsion springs. Double eye and Belleville springs.
9. Roller bearings and their load capacity and life. Combined and variable loading.
10. Adjusted bearing life equation. Tapered roller bearings. Bearing lubrication and design of housing.
11. Hydrodynamic lubrication theory. Hydrodynamic journal bearings.
12. Pressure-fed radial bearings. Boundary lubricated radial journal bearings. Pipes and fittings.
13. Summary of subject matter.

Guided consultation

43 hours, optionally

Syllabus

1. Load analysis, stress and strain analysis.
2. Failures resulting from static loading (ductile fracture).
3. Fatigue failure resulting from variable loading (fatigue fracture).
4. Stress analysis of shafts.
5. Strain analysis and vibration analysis of shafts. Joints for torque transmission.
6. Contact stresses and fatigue contact strength.
7. Analysis of statically and fatigue loaded tension joints with preload.
8. Bolted and riveted shear joints.
9. Welded joints.
10. Helical compression and extension springs.
11. Roller bearings.
12. Hydrodynamically and boundary lubricated radial journal bearings.
13. Summary of subject matter.